Key-fastener



(-No Model.)

W. F. BLANCHET. I KEY FA STENBR.

No. 577,504. Patented Feb. 23, 1897.

9 I 93 Fi =3.

00 mo mmma. wmmom UNITED STATES 'ATENT CFFTCE.

WVILLIAM F. BLANCHET, OF HAYVVARDS, CALIFORNIA, ASSIGNOR OF ONE- HALF TO THOMAS C. CREIGHTON, OF SAME PLACE, HENRY F. MARSH, JR OF ALAMEDA, AND ARTHUR KIDD, OF SAN FRANCISCO, CALIFORNIA.

KEY-FASTENER.

SPECIFICATION forming part of Letters Patent No. 577,504, dated February 23, 1897.

Application fil d March 14, 1896. Serial No. 583,238. (No model.)

To (tll whom, it may concern: Fig, 4 is a front iew, on an enlarged scale, Beit known that I, WILLIAM F. BLANOHET, of the fastener and the lower portion of the a citizen of the United States, residing at escutcheon-plate to which it is pivoted, the Haywards,in the county of Alameda and State fastener being turned into position against 5 of California, have invented certain new and the shank of the key, whichis shown in crossuseful Improvements in Key-Fasteners for section cut off close to the face of the escutch- Door-Locks, of which the followingis aspecieon-plate. Figs. 5 and 6 are detail views of fication. the key, showing the concave portion on the My invention relates toimprovements made shank of the key, Fig. 6 being a cross-section To in devices for confining a door-key in its lock at 90 00, Fig. 5. 6o

insuch manner that when the door is closed A indicates the escutcheon-plate of a morand the bolt of the lock is thrown the key cantise-lock, and a the keyhole in it. not be turned from the outside by the use of B is a fiat plate of oval or eccentricoutline nippers or other lock-picking instruments. having a rectangular open slot b in one side 15 The object of this invention is the producand a lever or straight member B on one tion of a device or attachment capable of beside of such slot. This piece B is secured to ing applied to the escutcheon-plate of most the front face of the escutcheon-plate by any of the present styles of door-locks now in means of a screw or a rivet C, on which as a the market, and possessing the function or pivot or center it is fitted to turn closely 20 quality of gripping the key with a powerwor againstthe face of the before-mentioned plate. force that increases under any attempt to This center of movement is placed below the turn the key backward. keyhole-aperture a and preferably on the ver- To such ends and object my said invention tical center line of the aperture, and the pivot consists in a gripping-plate of peculiar form is also located eccentrically in the piece B 25 and the combination thereof, with the eswith respect to the curved edge I), so that the cutcheon-plate, of a door-lock and with a key longer axis of the plate B being equal at least having a concave portion on its shank adaptto the shortest distance between the pivot 0 ed to engage the edge of said gripping-plate, and the top of the keyhole -aperture that the same being constructed and applied for opening will be covered by the plate B when 0 operation as hereinafter fully explained and it is turned on its pivot a sufficient distance. set forth. The open slot is situated on the side of the The following description explains at length shorter axis of the plate and is made of proper the manner in which I proceed to construct width to expose the keyhole-aperture, the and apply the said invention, reference being lower portion of which would be covered by 3 5 had to the drawings that accompany and form that part of the plate if the before-mentioned part of this specification. slot were not cut in the plate. From this In the said drawings, Figure 1 represents open slot the edge I) of the plate is formed on in front view the escutcheon-plate of a doora spiral or involute curve of increasing radius lock having my improved key-fastener sefrom such slot around to the opposite side of 40 cured to it, the said device being turned into the center. The lever B is formed integral the position which it assumes when the key with the plate 13, and its outer end is bent is to be introduced or removed from the lock. outward to form a handle portion 5 stand- Fig. 2 is a similar front view representing ing at right angles from the face of the plate the fastener turned into working position to for convenience in turning the plate on its 5 turn the key, which has previously been inpivot.

serted and turned in the lock, the shank of As thus constructed and applied, it will be the key being indicated in cross-section. Fig. seen that when the plate B is set into the po- 3 illustrates the position of the device when sition represented in Fig. 1 of the drawings turned down to act as an escutcheon or cover with the open slit in line with the keyhole- 50 for the keyhole after the key is removed. aperture of the look there is no obstruction IOO in the way of properly inserting and removing the key D of the look; but as the plate B is turned on its pivot O in the direction of the arrow 00 the curved edge I; is caused to pass across the keyhole-aperture, and if the key remains in the lock on that side of the door the edge I) will come in contact with the shank of the key, and suitable degree of force being applied to the lever B at such time this edge of the plate will press the keyshank against the edge of the circular part of the keyhole. By this means the shank of the key is gripped bet-ween the plate 13 and the edge of the aperture in the escutcheonplate, and by giving the edge I) sufiicient pressure against it the key will be held so firmly that it cannot be turned from the opposite side of the door by any implement or device of the burglar. In this position, which is represented in Fig. 2 of the drawings, it will be noticed that the backward rotary movement of the key at this time must tend only to increase the grip of the plate upon the keyshank. As the proper movement of the key to draw back the bolt being necessarily in the direction of the arrow y the plate B will move in the opposite direction (indicated by the arrow .2) if it moves at all. Such gripping action of the plate 13 is increased and made effective under all conditions by forming on the shank of the key, at that part which makes contact with the edge of the plate B,a concave recess or portion (Z, corresponding to 01' approaching in its cross-section the curve of the edge I) of the plate, as shown in Figs. 5 and 6 of the drawings. In addition to this oflice and function as a key-fastener my said attachment also forms a keyhole guard or escutcheon, entirely covering the opening when it is turned into the position represented in Fig. 3 after the key has been taken out. It also constitutes a convenient means of retaining the key in the look at other times by throwing the plate B partly around, so that the slot 1) is turned out of line with the keyhole.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

lhe herein-described key-fastening attachment for door-locks, comprising the segmentshape plate 13 having a curvilinear edge I), a rectangular slot b in one side extending from. the edge inward, and a straight arm or leX er B extending from the same side of the plate and in the same plane, the edge of said lever forming one side of such slot, and a hole C for a pivot-screw located to one side of the center of said plate and in close relation to the bottom of the rectangular slot as described; the said plate being pivotally attached to the escuteheon-plate of the lock at a point below and in line with the keyhole and eecentrically with relation to the curvi linear edge I) as described, whereby the slot in the plate is caused to register with the keyhole by turning the plate in one direction, and when turned in the opposite direction the plate is caused to cover the keyhole and its curvilinear edge to grip the shank of the key in the circular part of the keyhole, as and for the purpose set forth.

In testimony that I claim the foregoing I have hereunto set my hand and seal.

WILLIAM F. lllnlNCllIl'l. [1,. s]

Witnesses:

T. C. CBEIGHTON, FRED. J. RUssELL. 

